The group of four verses (13-16) sets forth God's mighty deeds; the next quartet of verses (17-20) tells of Israel's requital. It is significant of the thoughts which filled the singer's heart, that he begins the latter group with declaring that, notwithstanding such tokens of God's care, the people "went on to sin yet more," though he had specified no previous acts of sin. He combines widely separated instances of their murmurings, as he had combined distant instances of God's miraculous supply of water. The complaints which preceded the fall of the manna and the first supply of quails (Exod. xvi.), and those which led to the second giving of these (Numb. xi.) are thrown together, as one in kind. The speech put into the mouths of the murmurers in vv. 19, 20, is a poetic casting into bitter, blasphemous words of the half-conscious thoughts of the faithless, sensuous crowd. They are represented as almost upbraiding God with His miracle, as quite unmoved to trust by it, and as thinking that it has exhausted His power. When they were half dead with thirst, they thought much of the water, but now they depreciate that past wonder as a comparatively small thing. So, to the churlish heart, which cherishes eager desires after some unattained earthly good, past blessings diminish as they recede, and leave neither thankfulness nor trust. There is a dash of intense bitterness and ironical making light of their relation to God in their question, "Can He provide flesh for _His people_?" Much good that name has done us, starving here! The root of all this blasphemous talk was sensuous desire; and because the people yielded to it, they "tempted God"--that is, they "unbelievingly and defiantly demanded, instead of trustfully waiting and praying" (Delitzsch). To ask food for their desires was sin; to ask it for their need would have been faith.